scsi: smartpqi: correct stream detection

Correct stream detection by initializing the structure
pqi_scsi_dev_raid_map_data to 0s.

When the OS issues SCSI READ commands, the driver erroneously considers
them as SCSI WRITES. If they are identified as sequential IOs, the driver
then submits those requests via the RAID path instead of the AIO path.

The 'is_write' flag might be set for SCSI READ commands also.  The driver
may interpret SCSI READ commands as SCSI WRITE commands, resulting in IOs
being submitted through the RAID path.

Note: This does not cause data corruption.

Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Scott Teel <scott.teel@microchip.com>
Reviewed-by: Mike McGowen <mike.mcgowen@microchip.com>
Signed-off-by: Mahesh Rajashekhara <mahesh.rajashekhara@microchip.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
Link: https://lore.kernel.org/r/20240827185501.692804-3-don.brace@microchip.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index 54f7fe84344568ac1c0439876c12fdb3835afca5..8e2e71ab49aea5eb5eefe957fc228f81d957a156 100644 (file)
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -5942,7 +5942,7 @@ static bool pqi_is_parity_write_stream(struct pqi_ctrl_info *ctrl_info,
        int rc;
        struct pqi_scsi_dev *device;
        struct pqi_stream_data *pqi_stream_data;
-       struct pqi_scsi_dev_raid_map_data rmd;
+       struct pqi_scsi_dev_raid_map_data rmd = { 0 };
 
        if (!ctrl_info->enable_stream_detection)
                return false;